CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities:
Net loss	$ (588,078,000)	$ (56,254,000)	$ (310,826,000)
Adjustments to reconcile net loss to net cash provided by (used in) operations:
Depreciation and amortization	10,630,000	16,038,000	23,939,000
Provision for (benefit from) credit loss reserve	3,545,000	3,626,000	(413,000)
Stock-based compensation	23,673,000	40,766,000	28,076,000
Non-cash interest expense	6,060,000	2,914,000	5,281,000
Loss on debt extinguishment		1,333,000
Deferred tax (benefit) provision	(4,658,000)	7,597,000	97,287,000
Goodwill impairment	609,172,000	0	213,720,000
Unrealized foreign currency transaction (gain) losses	(1,454,000)	(3,393,000)	5,730,000
Other	(68,000)	(3,388,000)	385,000
Changes in operating assets and liabilities:
Accounts receivable	11,760,000	(16,964,000)	(6,590,000)
Prepaid expenses and other assets	(12,466,000)	28,192,000	(33,756,000)
Deferred costs	4,801,000	3,194,000	4,654,000
Accounts payable	(12,555,000)	5,774,000	157,000
Accrued expenses and other liabilities	27,874,000	(408,000)	(1,479,000)
Deferred revenue	(61,040,000)	(21,529,000)	(28,303,000)
Net cash provided by (used in) operating activities	17,196,000	7,498,000	(2,138,000)
Cash flows from investing activities:
Capital expenditures	(4,996,000)	(5,124,000)	(17,446,000)
Purchases of marketable securities		(18,025,000)	(31,757,000)
Sale and maturities of marketable securities	11,112,000	30,324,000	37,203,000
Payments for equity securities			(584,000)
Other investing activities	(1,737,000)	(1,355,000)	2,019,000
Net cash provided by (used in) investing activities	4,379,000	5,820,000	(10,565,000)
Cash flows from financing activities:
Proceeds from revolving credit facility		24,700,000
Payments of revolver credit facility		(24,700,000)
Proceeds from long-term debt, net of discount		210,000,000
Payments for long-term debt issuance costs	(419,000)	(17,176,000)
Principal payments of long-term debt		(198,438,000)	(6,250,000)
Common stock repurchases for tax withholdings for net settlement of equity awards	(9,865,000)	(4,894,000)	(49,003,000)
Principal payment of lease liabilities arising from a finance lease	(392,000)	(451,000)	(415,000)
Proceeds from the issuance of common stock	10,901,000	5,625,000	36,062,000
Net cash provided by (used in) financing activities	225,000	(5,334,000)	(19,606,000)
Effects of exchange rate changes on cash and cash equivalents	(1,469,000)	(1,677,000)	(1,272,000)
Net change in cash and cash equivalents	20,331,000	6,307,000	(33,581,000)
Cash and cash equivalents at beginning of period	101,154,000	94,847,000	128,428,000
Cash and cash equivalents at end of period	121,485,000	101,154,000	94,847,000
Supplemental information:
Cash paid for income taxes	10,180,000	11,185,000	12,273,000
Cash paid for interest	$ 6,028,000	$ 11,570,000	$ 9,088,000